class_docstr: For test code - build a dummy ResponseObservation proto.
code: def feature_units(self, feature_units):
      self._feature_units = feature_units
      return self
  
imports: import math
  import numpy
  from pysc2.lib import features
  from s2clientprotocol import raw_pb2
  from s2clientprotocol import sc2api_pb2
  from s2clientprotocol import score_pb2
label_desc: Use image node_id 11 for calling the Builder obj's underlying member method code with example usage: obj.feature_units(feature_units) and returns: self